This invention relates in general to apparatus for treating articles and deals more particularly with an improved return type automatic machine for electroplating, anodizing or cleaning articles of manufacture. A machine of the aforedescribed general type usually has an elevator-conveyor system which includes a plurality of arms supported in cantilever position for intermittent movement to work stations positioned along a continuous or endless path and for vertical movement relative to a series of treating tanks located along the path. Racks which support small articles to be treated and carried by the arms are moved into and out of the treating tanks by an elevator mechanism which comprises part of the elevator-conveyor system whereby the racked articles are successively moved from a loading and unloading station to and through a succession of work stations and returned to the loading and unloading station where the racks are automatically or manually handled. Such an automatic return type machine is well suited for treating articles which may be economically, individually handled. However, such machines as heretofore available lack the capability of treating articles in bulk. Accordingly, it is the general aim of the present invention to provide an improved automatic return type machine capable of plating, anodizing or cleaning small work pieces in bulk which cannot be otherwise economically handled.